# How do you find a tangent line parallel to secant line?

##### 1 Answer

You can find a tangent line parallel to a secant line using the Mean Value Theorem.

The Mean Value Theorem states that if you have a continuous and differentiable function, then

To use this formula, you need a function

I'll also use

So, we know that the slope of this line will be

To find the tangent lines parallel to this secant line, we will take the function's derivative,

Solving this for

So, the lines tangent to